Multiple linked sustainable drainage systems in hydrological modelling for urban drainage and flood risk management

Assessing the performance of future urban drainage management practices requires novel hydrological modelling approaches that can handle a large number of spatially distributed measures, such as sustainable drainage systems (SUDS). This paper presents the implementation of a SUDS modelling approach in a semidistributed hydrological model that enables the simulation of flow among multiple linked SUDS and meso-scale retention spaces and the application of this model to an urban catchment. The objectives of the implemented model are the representation of SUDS as model elements with water redistribution functionality as well as its possible integration into a flood risk management tool. The model was applied to quantify the impacts of socio-economic and climate change in an urban catchment in Hamburg, Germany, under different future scenarios and combinations of SUDS. The results demonstrate the potential of SUDS and multipurpose retention spaces for flood risk mitigation.